U.S. patent number 7,329,266 [Application Number 10/521,422] was granted by the patent office on 2008-02-12 for surgical clamps.
This patent grant is currently assigned to Research Surgical Pty Ltd. Invention is credited to David Berry, Brett Hamilton, Michael Kerr, Alistair Royse.
United States Patent |
7,329,266 |
Royse , et al. |
February 12, 2008 |
Surgical clamps
Abstract
An arterial clamp has opposed clamping posts arranged to lie at
opposite sides of an artery to clamp the artery between opposed
clamping faces of the posts. The posts are carried by a pair of
arms pivotally movable one relative to the other to move the posts
into clamping relationship with the artery. A ratchet device
releasably locks the arms in a selected clamping position. The
clamp including posts, arms, and ratchet device is formed as a
one-piece plastics moulding.
Inventors: |
Royse; Alistair (Eltham,
AU), Hamilton; Brett (Tooradin, AU), Berry;
David (North Ringwood, AU), Kerr; Michael
(Ivanhoe, AU) |
Assignee: |
Research Surgical Pty Ltd
(Victoria, AU)
|
Family
ID: |
25646764 |
Appl.
No.: |
10/521,422 |
Filed: |
July 26, 2002 |
PCT
Filed: |
July 26, 2002 |
PCT No.: |
PCT/AU02/00996 |
371(c)(1),(2),(4) Date: |
September 23, 2005 |
PCT
Pub. No.: |
WO03/011150 |
PCT
Pub. Date: |
February 13, 2003 |
Prior Publication Data
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|
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Document
Identifier |
Publication Date |
|
US 20060129170 A1 |
Jun 15, 2006 |
|
Current U.S.
Class: |
606/158 |
Current CPC
Class: |
A61B
17/122 (20130101) |
Current International
Class: |
A61B
17/08 (20060101) |
Field of
Search: |
;606/158,151,157
;251/10 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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2183998 |
|
Feb 1998 |
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CA |
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735245 |
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May 1980 |
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SU |
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Other References
International Search Report for PCT/AU2002/000996; ISA/AU; Mailed:
Sep. 25, 2002. cited by other.
|
Primary Examiner: Hayes; Michael J.
Assistant Examiner: Gettman; Christina
Attorney, Agent or Firm: Harness, Dickey & Pierce,
PLC
Claims
The invention claimed is:
1. A clamp for surgical use, the clamp comprising a pair of arms
pivotally interconnected at adjacent ends for pivotal movement in a
plane between an open configuration in which the arms define a
V-shaped configuration and a closed configuration in which the arms
are approximately parallel, and a ratchet device located generally
opposite of the interconnection of the arms and operative during
closing movement to retain the arms in a selected, closed
condition, wherein each arm has a clamping member in the form of a
post located on the arm between the interconnection of the arms and
the ratchet device and extending therefrom substantially
perpendicularly to the plane of pivotal movement whereby distal
ends of the posts extend outside of the plane, each of the two
posts having a clamping face whereby an artery can be clamped
between the respective clamping faces of the two posts as the arms
are moved to the closed configuration.
2. A clamp according to claim 1, wherein the clamping faces are
each inclined relative to the axis of the post by an angle of
approximately 4.degree. to 6.degree. so as to converge at an
included angle of approximately 8.degree. to 12.degree..
3. A clamp according to claim 1, wherein the clamping faces of the
clamping posts converge in a direction towards the distal ends of
the posts.
4. A clamp according to claim 3, wherein the clamping faces are of
substantially planar form.
5. A clamp according to claim 4, wherein the clamping posts are
each of a tapered shape, narrowing towards its distal end.
6. A clamp according to claim 4, wherein the clamp is formed as a
one-piece plastics moulding with the pivot being formed by a hinge
consisting of a flexible web of plastics material interconnecting
the adjacent ends of the two arms, and the ratchet device is formed
by interengageable ratchet teeth formed on the respective arms, the
teeth being disengageable to release the clamp by flexing movement
permitted by the inherent flexibility of the plastics material from
which the clamp is formed.
7. A clamp for surgical use, the clamp comprising a pair of arms
pivotally hinged at adjacent ends for pivotal movement in a plane
between an open configuration in which the arms define a V-shaped
configuration and a closed configuration in which the arms are
approximately parallel, and a ratchet device spaced from the hinge
and operative during closing movement to retain the arms in a
selected, closed, condition, wherein each arm has a clamping member
in the form of a post having a clamping face, wherein each post is
positioned between the hinge and the ratchet device and extends
from the arm substantially perpendicularly to the said plane of
pivotal movement whereby the posts with their clamping faces extend
beneath the arms whereby an artery lying beneath the arms can be
clamped between the clamping faces of the two posts as the arms are
moved to their closed position.
8. A surgical clamp comprising: a pair of arms connected at a hinge
located at a first end of said clamp, said arms pivotally movable
in a plane between an open configuration in which said arms define
a V-shaped configuration and a closed configuration in which said
arms are approximately parallel; a ratchet device located at a
second end of said clamp generally opposite said hinge, said
ratchet device operable during closing movement of said arms to
retain said arms in a selected, closed, condition; said arms each
including a clamping member comprising a post having a clamping
face and extending from said arm substantially perpendicularly to
said plane, said post located intermediate said hinge and said
ratchet; and wherein a vessel can be clamped between the respective
clamping faces of said posts as said arms are moved to their closed
position.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
This Application is a U.S. National Stage of International
Application No. PCT/AU2002/000996 filed 26 Jul. 2002 and published
in English as WO 03/011150 A1 on 13 Feb. 2003. The disclosure(s) of
the above application is incorporated herein by reference.
The present invention relates to clamps for surgical use, both
human and veterinary. More particularly the invention relates to
clamps for occluding coronary arteries and other arteries used to
perform bypass grafts to coronary arteries, being suitable also for
use with other vessels or tube-like structures of generally similar
dimensions in humans or animals to compress the structure to
prevent passage of blood or other fluid.
When performing "off pump" coronary artery bypass surgery (CAGS),
the intention is to perform the bypass without stopping the heart.
Therefore it is necessary to occlude the coronary artery by means
of clamps on either side of a small incision made in the artery to
which the bypass artery conduit will be sewn. Accordingly blood
flow is temporarily prevented to part of the heart whilst the
grafting is being performed. Subsequently, the clamps are removed
and the coronary artery then receives supplementary blood flow via
the graft.
One form of existing clamp for this purpose is a plastic derivation
of the traditional metal "bulldog" clamp but smaller and lighter.
It works by being opened with finger pressure and closed by the
inherent resilience of the material. Frequently, the clamping
pressure provided is not sufficient to adequately control blood
flow. Also it is relatively long, making it difficult to fit easily
within the stabilizing arms of an associated retractor device. It
can become displaced perpendicularly to the heart such that it
impedes the vision of the surgeon as well as catching the suture
thread during grafting. Metal versions of the clamp also suffer
from disadvantages due to their weight which results in
counter-forces existing due to their inertia when attached to the
moving heart. Consequently, they also frequently dislodge. Their
greater size makes placement in confined spaces even more
difficult.
Existing clamps for use on the conduits (arteries to be used as
grafts) tend either to be the metal version of the "bulldog" clamp
or a plastic spring-loaded clamp. The weight of the metal clamps
results in substantial "drag" on the conduit during grafting which
adds to the difficulty of the graft. The plastic spring-loaded
clamp comprises spring-loaded vice-like jaws and is larger and its
bulk makes it less suitable in confined spaces, resulting in
additional and redundant lengths of conduit being required where
more than one graft is performed for each conduit (sequential
anastomoses).
According to the present invention, there is provided a clamp for
surgical use comprising opposed clamping members pivotally movable
one relative to the other between an open condition and a closed
clamping condition, and a ratchet device operative during closing
movement to retain the clamping members in a selected, closed,
clamping condition.
Advantageously, the ratchet device comprises a series of ratchet
teeth in an arcuate array centered on the axis of pivotal movement
of the clamping members, and a ratchet tooth movable with one of
said clamping members upon pivotal movement of that clamping member
relative to the other clamping member to move along the array of
ratchet teeth to be retained thereby in a selected clamping
position.
A particularly preferred embodiment of the invention comprises a
pair of arms pivotally interconnected at adjacent ends for pivotal
movement between an open configuration in which the arms define a
V-shaped configuration and a closed configuration in which the arms
are approximately parallel, one of the arms having at its end
remote from the pivot the ratchet tooth and the other arm having on
its end remote from the pivot a limb formed with said array of
ratchet teeth with which the ratchet tooth engages upon closure of
the two arms, each of the clamping members being carried by a
respective one of the two arms.
Advantageously, the clamping members are of post-like form
extending in a plane directed transversely to a plane containing
the arms of the clamp.
Particularly advantageously, clamping faces of the opposed clamping
members are inclined one relative to the other so as to converge in
a direction towards tip portions of the clamping members. In one
embodiment, the clamping faces are each inclined to the
perpendicular by an angle of approximately 4 to 6.degree. so as to
converge at an included angle of approximately 8.degree. to
12.degree.. This convergence facilitates retention of the
clamp.
Advantageously, the clamp is formed as a one-piece plastics
moulding with the pivot being formed by a hinge consisting of a
flexible web of plastics material interconnecting the adjacent ends
of the two arms.
According to another aspect of the invention, there is provided an
arterial clamp comprising opposed clamping posts arranged to lie at
opposite sides of an artery to clamp the artery between opposed
clamping faces of the posts, the posts being movable into clamping
relationship with the artery by arcuate movement of one post
relative to the other about a hinge zone, and a device for
releasably locking the clamping posts in a selected clamping
position, the clamp being formed as a one-piece plastics
moulding.
An embodiment of the invention will now be described, by way of
example only, with reference to the accompanying drawings, in
which:
FIG. 1 is a plan view of a clamp in accordance with the preferred
embodiment of the invention;
FIG. 2 is a schematic view of the clamp looking in the direction of
arrow A in FIG. 1;
FIG. 3 is a detail looking in the direction of arrow B in FIG. 1
and showing a clamping post;
FIG. 4 is a detail view of the clamping post at right angles to the
view of FIG. 3; and
FIG. 5 is a transverse section through the clamping post.
An arterial clamp in accordance with the preferred embodiment of
the invention is formed as a one-piece moulding in a suitable
plastics (for example, homopolymer polypropylene or acetal
copolymer) and consists of opposed arms 2, 4 pivotally connected at
one end by a hinge 6 formed by a flexible web of the plastic
material so as to be movable from a substantially V-shaped open
configuration as shown in FIG. 1, to a closed clamping
configuration in which the arms 2, 4 are approximately parallel.
The outer end of the arm 2 is formed with a projecting limb 8
having on its inner face a set of ratchet teeth 10, the teeth 10
extending along a curved path centered on the pivotal axis of the
hinge 6 connecting the two arms 2, 4. The outer end of the arm 4 is
formed with a ratchet tooth 12 to co-operate with the ratchet teeth
10. Each of the arms 2, 4 is formed with a clamping post 14
projecting substantially perpendicular to the plane of the arms 2,
4, the posts 14 forming the actual clamping members of the clamp.
In use, the two posts 14 lie on opposite sides of the artery and to
clamp the artery the two arms 2, 4 are closed by pivotal movement
about the hinge 6 with the ratchet tooth 12 at the end of the arm 4
moving along the ratchet teeth 10 on the projecting limb 8 until
the required clamping condition has been attained, with the arms 2,
4 being positively held in that condition by the one way action of
the ratchet teeth.
The clamp is able to be positioned, manipulated, and closed by
forceps or the like engaging the outer sides of the two arms 2, 4
for which purpose the sides are preferably provided with a series
of small projections 16 along their length to facilitate retention
by the forceps. The arms 2, 4 are each also provided with holes 18
for receiving the tips of the forceps, to provide further
versatility.
With the clamp described above, the surgeon can apply whatever
clamping pressure is considered appropriate to stop fluid flow and
once applied, that pressure will be maintained due to the locking
effect provided on the two arms 2, 4 by the ratchet action provided
by the interengaging teeth 10, 12. To release the clamp, all that
is necessary is to displace the projecting limb 8 laterally out of
the plane of the second arm 4 to thereby release the teeth 10 from
engagement with the tooth 12. This can readily be achieved due to
the inherent flexibility of the plastics material.
In the embodiment shown, the two clamping posts 14 are of tapered
shape, narrowing towards their distal end. The clamping face 14a of
each post 14 is a planar face and the post 14 is elongated in
transverse cross section, with the elongation serving to maximise
the resistance to deflection of the clamping post 14 under the
clamping pressures. The clamping face 14a may be formed with a
series of very small ridges or depressions to facilitate improved
grip between the face and the tissue. The distal or tip end of each
clamping post 14 may also be provided with a small lip to aid
retention. Although the clamping posts 14 may extend in a plane at
right angles to the plane of the arms 2, 4, alternatively they may
be positioned in a plane inclined out of that 90.degree. plane and
away from the ratchet limb 8 so that the ratchet limb 8 is "lifted"
a little further away from the zone of clamping of the two clamping
posts 14.
Although in the embodiment illustrated, the clamping faces 14a of
the two posts 14 are substantially parallel and perpendicular to
the plane of the arms 2, 4, we have determined that it is
particularly advantageous for the two clamping faces to converge in
a direction towards their tip ends. Typically, each clamping face
is inwardly inclined relative to the perpendicular by approximately
4 to 6.degree. to provide an included angle of convergence between
the two clamping faces of approximately 8 to 12.degree.. This
convergence although relatively small causes greater clamping force
to be exerted at the tip portions and significantly facilitates
retention on the artery. In the fully closed condition of the clamp
the tip ends of the posts 14 engage at their clamping faces and
deflect slightly.
By way of illustration, the length of the clamp from the hinge 6 to
the outer side of the ratchet limb 8 is about 10 mm which makes the
clamp significantly smaller than the existing forms of clamp
previously discussed, this substantial size reduction being
obtained due to the basic shape as illustrated incorporating the
locking ratchet mechanism. Accordingly, the ratchet mechanism not
only allows the clamping force to be controlled and maintained it
is also used to achieve a substantial reduction in overall length
which allows for easier positioning in confined spaces.
The shape of the clamp makes it much less prone to projecting
perpendicular to the surface of the heart and so less prone to
catching the suture material during the construction of the
anastomosis. The plastic construction reduces the weight
substantially in comparison to metal and therefore the clamp will
easily move with the heart and so not be prone to dislodgement
consequent on heart motion; nor will this drag the conduit
excessively if used to occlude the conduit.
It is envisaged that the clamp would be single use only and not
intended for re-cleaning and re-sterilization. In fact
re-sterilization would be very difficult due to the presence of the
depressions/holes provided to allow the clamp to be grasped by
forceps or other devices to allow positioning and tightening,
preventing adequate cleaning and removal of blood from the
clamp.
It would be intended that two such clamps would be used to occlude
a single coronary artery and a further one for the conduit. Within
each operation, the clamps could be used on more than one coronary
artery.
The size of coronary arteries grafted ranges from 1.0 mm to 2.5 mm
in diameter, with most being 1.5-2.0 mm. The size of conduits
usually ranges from 1.75 mm to 3-4 mm. These sizes would be
relatively similar to many arteries or veins used in other forms of
vascular or plastic surgery where arteries are being joined
together or transplanted. In other disciplines of surgery, arteries
of this size are frequently encountered and sometimes, temporarily
occluded for varying reasons or alternatively joined together.
Consequently, even without any modification, the clamp may have
potential use outside of "off pump CAGS". Size or other minor
changes to the design, may allow an even broader range of
applications for the clamp for other surgical procedures on humans
or on animals.
The embodiments have been described by way of example only and
modifications are possible within the scope of the invention.
* * * * *